In the telecommunications industry when optical fibers in a cable need to be broken out from the main cable or active electronics need to be added into the system, this requires splitting open the optical fiber cable. The split open cable needs to be sealed. Although it is easier to seal a cable going into or out of the closure with a circular hole or passage, it is often necessary for working room to use an oval port which presents a more complex sealing problem. The seal may be included in an in-line closure where the fiber cable comes in one side of the closure and either a new cable or the original cable emanates from the other side of the enclosure or what is known as a "butt" splice closure where the cable or the cable it is spliced to is put into one side of the enclosure and re-emanates from the same side of the closure base member with generally a dome shaped top that attaches to the base member, i.e. the portion of the closure where the cables enter or exit. U.S. Pat. No. 5,155,794 and U.S. application Ser. No. 08/008,227 , now U.S. Pat. No. 5,235,337, (WO 90/08336); and U.S. Pat. No. 5,097,530 describe preferred optical fiber butt splice closures. A butt splice closure with an integral but detachable electronics package is described in Ser. Nos. 07/439,898, abandoned, and 08/000,991,now U.S. Pat. No. 5,261,024. The disclosures of each of these patents or applications are completely incorporated herein by reference for all purposes into this specification.
Because of common trenching "gas lines and communication lines in the same trench", there has been a tendency to seek a non-heat shrinkable sealing, i.e. cold applied sealing product for those places where the cables enter and exit from the closure. Since heat shrinkable materials are fast, efficient, and provide excellent sealing with additional benefits of long lifetime and strain relief, creating a cold applied closure that can be installed over a wide variety of temperature ranges and provide sealing when subjected to repeated thermal cycling from -40.degree. C. to +60.degree. C., optionally, under a positive pressure is difficult. Creating a mechanical cold seal which can be applied in a restrictive base environment wherein the base may be only a foot or less across is even more complex.